What's wrong on taking this XML element?

XML:

<entry xmlns="http://www.w3.org/2005/Atom" xmlns:gd="http://schemas.google.com/g/2005" xmlns:media="http://search.yahoo.com/mrss/" xmlns:yt="http://gdata.youtube.com/schemas/2007">
    ...
   <author>
      <name>Seamless</name>
      <uri>https://gdata.youtube.com/feeds/api/users/SeamlessR</uri>
   </author>

Code:

var ns = XNamespace.Get("http://www.w3.org/2005/Atom");
var name = xDoc.Descendants(ns + "entry").First().Element("author").Element("name").Value;

it says Object reference not set to an instance of an object.

Jon Skeet
people
quotationmark

You're using Element("author") and Element("name") as if they're not in a namespace. The namespace will have been defaulted to the same namespace as entry, so you want:

var ns = "http://www.w3.org/2005/Atom"; // Just use an implicit conversion
var name = xDoc.Descendants(ns + "entry")
               .First()
               .Element(ns + "author")
               .Element(ns + "name")
               .Value;

people

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